Expansion and contraction joint



Aug. 13, 1946. C, MORTENSQN 2,405,844

EXPANSION AND GONTRACTION JOINT Filed Nov. 29, 1944 ggf-p3. l

Patented Aug. 13, 1946 UNITED STATES PATENT GFFICE EXPANSION ANDCONTRACTION JOINTl` Gunnar C. Mortensen, Chicago, Ill.

Application November 29, 1944, Serial No. 565,673

6 Claims.

My invention is directed to expansion joints for concrete or compositionpavements or for walls, the illustration in the drawing exemplifying oneparticular form thereof adapted for concrete pavements, roads or thelike.

One of the objects of my present invention is the provision of anexpansion joint unit or structure which is adapted to be manufactured,packed and shipped with its respective parts maintained separately andunassembled, and which have structural features providing for quick andeasy assembly on the location of the job with a minimum amount of laborand adapted tc meet varying conditions of particular jobs.

A further object of my invention is the provision of an inexpensiveexpansion joint for roads, pavements or walls which is formed of anovelly bent and fabricated strip member made of a continuous singlepiece of metal fabric, or of a foraminated sheet having spaces thereinof sufcient size to permit inflow and locking engagement of sand, gravelor other particles of the wet poured concrete. The said novel expansionjoint includes a pair of oppositely directed integral base membersformed from the edge portions of the metal/fabric strip, and through thespaces of which suitable spikes, stakes or the like may be driven toengage into the ground or other supporting surface to temporarilysupport and secure the expansion joint in its desired position preceding the pouring of the concrete. f

A further object of my invention is provision of an `expansion jointhaving the aforesaid base elements or members as well as oppositely andtransversely extending anchoring flanges or anchoring webs which arepreferably formed integral with the intermediate part of the sheet orstrip of metal fabric, the said joint having a doubled back centralportion or vertex which is normally disposed in a position a shortdistance below the upper level of the pavement or road so as to providespace for reception of a sealing plastic or equivalent material to sealthe joint against entry of water and moisture.

Other and further objects of my invention will be apparent from thefollowing description and amended claims:

On the drawing:

Fig. 1 is a perspective view of a relatively short section of oneembodiment of my invention and which normally may be made from a singlefabric strip.

Fig. 2 is a short section of a form of my metal expansion joint shown asanchored in .and between two adjacent end 2 portions of concrete roadslabs. f

Fig. 3 is a cross sectional view of a road joint showing the adjacentend portions of two concrete slabs and illustrating a sealing elementthereabove having a substantially concave sur.- face.

Fig. 4 is a perspective and cross sectional View of a fragment of avertically or upwardly extending wal1 illustrating one manner in whichmy novel joint may be mounted and anchored in the adjacent end sectionsof a concrete wall or the like.

Fig. 5 is a perspective and fragmentary view of an arch or dowel supportmade from a section of metal fabric and illustratingv the position ofthe originally flat metal fabric after the same has been bent along atransverse line in the course of- -manufacture of the expansion joint iillustrated in' Fig. 6, Fig. 46 is a cross sectional view illustratingmy metal fabric expansion joint in normal positions y in the adjacentendsections of typical concrete slabs and wherein such joints includeconnected metal fabric supports which are adapted to hold a dowel rod insupported position extending from one concrete slab to the other andextending through the substantially central portion of my metal fabricexpansion joint.

Referring to the drawing, particularly Figs. 1 to 3 inclusive, referencenumeral I0 generally designates the rounded ridge which is formed byfolding or doubling vback adjacent sections of the metal fabric,-preferablywoven fabric, and reference numerals l2 and I3 designate theintegral downwardly extending wall sections The metal fabric is thenbent horizontally in opposite directions as indicated and then doubledback upon themselves to form transversely and substantially horizontallyextending anchors, webs, wings or flanges i4 and i5 respectively.

, As illustrated in Figs. l to 4 inclusive, the doubled back outer edgesof the webs or anchoring flanges I4 and I5 are preferably thoughoptionally bent or crimped upwardly along longitudinal lines a shortdistance inward from the doubled back edges to thereby form upturnedflanges I5 and Il respectively. The upwardly extending direction ofthese facilitate running or flowing of wet concrete into the spacestherebelow,

As shown in Figs. 1, 2 and 3 respectively, reference I8 and `lildesignate lupwardly and downwardly extending integral wall sectionswhich preferably form a continuation of the doubled back webs I4 and l5respectively, that is, ex-

tending from the underside of the anchoring webs or ilanges I4 and I5respectively. Said downwardly extending wall section I8 and I9 extend ashort distance, preferably in substantial alignment with the upper wallsections I2 and I3 respectively, and extend to corners which may varyperceptibly in angle, though which are illustrated in Figs. 2 and 3 asbeing substantial right angles. The wall sections I8 and I9 merge intothe substantially horizontally bent and directed oppositely extendingbase flanges or wings 2I and 22 which comprise the lateral edge areas 4inverted V. As illustrated in Figs. 5 and 6 the said arched supports areformed of a Woven metal fabric bent substantially in the mannerillustrated in Fig. 5 to form an upper apex extending longitudinally.The lateral edges thereof are -bent forming ground engaging flangeswhich rest on the supporting ground or other surface. ,Only a fragmentof the entire metal fabric support is illustrated in Fig. 5, it beingunderstood that the same may extend from one lateral edge of thepavement or slab to the opposite lateral l edge. One of said archedsupports is positioned of the entire unit and which are of a dimensionso that the same preferably extend at least as far as the outer edgeportions of the anchoring webs or iianges I4 and I5. i

When it is desired to mount or position the said expansion joint uponthe support ground or other base which has been leveled to the desireddegree, the said expansion joint unit is placed in upstanding position,as illustrated in Figs. 1 to 3 inclusive, and the same preferablysecured by spikes, stakes or the like which are 'designated as 24 andwhich are driven through apertures of the edge portion of the bases orlflanges 2I and 22 at suitably spaced apart intervals to thereby mountsaid expansion joint unit so that the same will not move when theconcrete mix is poured from either or both sides thereof. Referencenumerals 25 and 26 designate or illustrate slabs of concrete only thefragmentary end sections of which are illustrated.

When the wet concrete mix is poured the same will readily run into thespaces between the bases 2l and 22 and the respective flanges I4 and I5,and as the expansion joint unit is formed of either woven wire fabric orforaminated metal,

vthe stone, gravel and rock of the concrete mix readily positionthemselves in the spaces or apertures of the metal fabric and uponsetting the anchoring webs or flanges I4 and I5 become firmly embeddedand anchored in the adjacent slabs, and also as the concrete mix runspartially into the apertures of the metal fabric of the remaining partsof the expansion joint other than the ridge, the said respective partsuponsetting of the mix, become secured to the respective slabs.

Preliminary to the pouring of the concrete mix about, adjacent and uponthe joint which normally extends from one edge of each slab to the otheredge, it is desirable to place suitable strips 'ofiwood or the likedirectly upon the ridge I0 so as to prevent the wetY concrete mix fromrunning over and upon the said ridge and so that upon later removal ofsaid strip a relatively sha1- low space will be thereby provided for thereception of any suitable' yieldable bituminous or mastic composition,or of a preformed sealing strip of yieldable mastic material which isgenerally designated Figs. 3 and 6 by the reference in numeral 21. Theobject and accomplishment of yieldable sealing element 21 is to preventthe entry of Water into the space between the concrete slabs. In thecase of uses of my expansion joint in vertical` walls ther said sealingelement or strip 21 may be suitably mounted in the space between theridge I0 and the corners of the slabs at the side surface of said slabs,as illustrated in Fig. 4.

In Fig. 6 I have illustrated one embodiment of my invention wherein theexpansion joint unit `includes. a plurality of or pair of archedsupports or chairs 28 which may be formed of wire or metal rods orfabric bent into the shape of an each ,side of the expansion jointmember as shown in Fig. 6, preferably with the flanges thereofoverlapping the base flanges 2l and 22 respectively. As is shown in Fig.6, spikes 24 which hold or secure the central expansion joint memberalso are driven through the overlapped lateral edge areas of theadjacent arched support edges. One of the edge flanges of each archeddowel rod support is superposed upon the base flanges of said expansionjoint. The said arched supports or stools 23 provide supporting meansfor suitable dowel rods 3U which extend from within onev concrete slabinto the other as illustrated in Fig. 6. Said dowel rods 30 extendthrough suitable holes or interstices in the down- 'wardly extendingwall sections I8 and I9. As in the case where the spaces of the wirefabric are suicient the dowel rods are merely inserted therethrough. I

As illustrated in Fig. 6, and in order to provide for longitudinalmovement and of the dowel rods, or of the concrete slabs With respect tosaid dowel rods, a suitable substantially cylindrical sleeve-like cap 32is mounted over one end and over each of said dowel rods 30 preliminaryto the pouring of the concrete, and the cylindrical caps 32 are sopositioned that a space remains between the ends of each dowel rod andthe .closed end of its metal cap. Such space is suicient to provide forany normal expansion of `the concrete slab. The end of each dowel rodnts reasonably snugly though to such degree that it forms a slidablebearing with the interior surface of the metal cap 32 mounted thereon.

As illustrated in Figs. 5 and 6, arched metal bails 33 are providedwhich are secured upon the apices of the arch supports 28 respectivelyat such spaced apart intervals as is desired in order to temporarilymount and retain the respective dowel rods 30 preliminary to the drawingand pouring of the concrete mix. The said bails 33 may be formed of wireor the like and will prevent rolling or undesirable movement of thedowel rods before or during the pouring of the mix.

As shown in cross section in Fig. 2, I provide a channel-like metal capor sealing element 34 which is preferably pressed from a single strip ofsheet metal of the desired length and which is quickly and easilypositioned upon and about the ridge II) of the expansion joint and sothat the respective depending integral edge flanges 35 thereof eitherrest upon or engage the upper portion of said expansion jointsubstantially. Seal-l ing caps 34 such as exemplified in Fig. 2 arepositioned upon the respective expansion joints by merely pressing thesame thereon so that the lside anges 35 pinch and frictionally engagethe upper portion of the respective expansion joints the levelling ofthe upper surface of the concrete to the desired height. The saidsealing caps 34 may be suitably corrugated, if desired or perforated(not shown) in instances where the builder desires to leave them inposition permanently to form part of the expansion joint. It will beunderstood that the expansion on the adjacent slabs will likewisecompress the side portions of said sealing caps simultaneously with thecompression of the remaining parts of the entire expansion joint.

In instances where it is desired to mount a sealing cap of a suitablemastic composition, the builder may readily remove the metal sealingcaps 34 by pulling the same upwardly and then pouring or pressing in thedesired mastic material to form sealing caps such as illustrated at 2li,for example, in Figs. 3 and 6.

My invention provides a satisfactory means wherein the sealing effect ofthe expansion joint and cooperating cap between the respective adjacentends of road slab sections is maintained regardless of the change ofsize of the space between said slab sections to the expansion andcontraction.

The present invention has been described herein more-or-less previouslyas to details. Yet it is t0 be understood that it is not to be limitedthereby, as changes in proportions and substitution of equivalents maybe made without departing from the spirit and scope of the invention.

I claim:

l. In a device of the kind described, an expansible joint for providinga space between the ends of adjacent slab sections, said joint beingcomposed of metal fabric comprising a stool-likeV member formed of asingle metal fabric strip and having downwardly extending spaced apartwall sections merging in an upper ridg an outwardly extending anchoringflange formed integral with each of said wall sections; and base flangesextending oppositely and outwardly from the lower portions of said wallsections to temporarily support said expansion joint units.

2. In combination with a pair of concrete sections located substantiallyadjacent each other, an expansion joint formed of a metal fabriccomprising a doubled back stool-like member formed of continuous metalfabric strip and having spaced apart iiexible side walls depending froma common ridge; the lowermost edge areas of said joint being outwardlybent at substantially right angles to provide base flanges; andoppositely and transversely extending anchoring webs extending from theintermediate portions of said depending side walls and adapted to beembedded in said slabs respectively; and a channel-like cap membersuperposed upon said expansion joint ridge and having its upper surfacein substantial alignment with the upper surface of said slabs.

3. In combination with a pair of concrete sections located substantiallyadjacent each other, an expansion joint formed of a metal fabriccomprising a doubled back stool-like member formed of continuous metalfabric strip and having spaced apart flexible side walls depending froma common ridge; the lowermost edge areas of said joint being outwardlybent at substantially right angles to provide base anges; and oppositelyand transversely extending anchoring webs extending from theintermediate portions of said depending side walls and adapted to beembedded in said slabs respectively.

4. In combination with a pair of concrete sections located substantiallyadjacent each other, an expansion joint formed of a metal fabriccomprising a doubled back stool-like member formed of continuous metalfabric strip and having spaced apart flexible side walls depending froma common ridge; the lower-most edge areas of said joint being outwardlybent at substantially right angles to provide base flanges; oppositelyand transversely extending anchoring webs eX- tending from theintermediate portions of said depending side walls and adapted to beembedded in said slabs respectively, and dowel rods extending throughsaid side walls and adapted to be embedded in the adjacent concreteslabs.

5. In combination with a pair of concrete sections located substantiallyadjacent each other, an expansion joint formed of a metal fabriccornprising a doubled back stool-like member formed cf continuous metalfabric strip and having spaced apart flexible side walls depending froma common ridge; the lower-most edge areas of said joint being outwardlybent at substantially right angles t0 provide base flanges; oppositelyand transversely extending anchoring webs eX- tending from theintermediate portions of said depending side walls and adapted to beembedded in said slabs respectively, dowel rods extending through saidside walls and adapted to be embedded in the adjacentsections, andexpansion caps slidably mountedon ends of said dowel rods respectively.

' 6. In a device in the kind described, an expansible joint for sealinga space between the ends of adjacent slab sections, said joint beingcomposed of metal fabric comprising a stool-like member formed of asingle metal fabric strip and having downwardly extending spaced apartwall sections merging in an upper ridge; an outwardly extendinganchoring flange on each of said wall sections and formed by bendingoutwardly and dOublIlg back Said wall sections respectively and baseflanges extending oppositely and outwardly from the lower portions ofsaid wall sections and adapted to temporarily support said expansionjoint units.

GUNNAR C. MORTENSON.

